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Huck1969
January 4, 2010, 12:42 AM
I would really appreciate help from the M14 and M1A experts on the forum.
My neighbor bought an M1A from a local gun store several years ago that specializes in "precision" long range rifles and he has had a continued problem with it stove piping cases. He has taken it back to the store and they claim to have sent it to a gun smith and had it "fixed" a couple of times but the problem persists. Specifically it seems to stove pipe after firing and ejecting about four rounds successfully. I don't know if this is due to heat build-up or fouling in the action. I have heard about a possible replacement fitting that allows the shooter to adjust the amount of gas ported to work the action. Is there such a thing and do you think that would remedy the problem?

tINY
January 4, 2010, 01:46 AM
Two places to check - the ejector and the op-rod/piston.

Check that the ejector in the face of the bolt pushes down (hard) and snaps back. With a live round, and the gun pointed down-range, see if the cartridge is extracted and flipped out of the action when you draw the charging handle back slowly. It should drag on the right side of the chamber on its way out.

The piston and gas port should be relatively clean and move freely. Check the op-rod for smooth movement. There is an op-rod guide that can cause problems if the roll-pin that holds it to the barrel gets crushed or bent.

And make sure that the roller on the bolt is properly greased.



-tINY

FALacy
January 4, 2010, 02:14 AM
Try new magazines.

10-96
January 4, 2010, 03:30 AM
+1 on the new mag suggestion. If he isn't using SA or other top quality mags- then malfunctions ought to be expected not suspected.

The other thing- does he grease and lube the rifle properly? Mine runs funky when I don't grease it well per instructions. Grease- not just oil.

And, it isn't AK type material so it needs to be tolerably clean.

madcratebuilder
January 4, 2010, 01:19 PM
A magazine should not effect stove piping. If it's feeding ammo it's doing it's job. Stove piping is the bolt not traveling completely rearward but just far enough to pick up the nest round.

More info would be helpful, what ammo? Is the rifle stock or modified in any way?

You need a usgi extractor, the stock SA one is suspect at best.
How does the op-rod fit the op-rod guide? Hows the spring and the spring guide? Is the gas cylinder clean, is the piston worn? Is the gas port in the cylinder aligned with the barrel port?

Are you using rifle grease on the bolt and roller and the op-rod and guide?

azredhawk44
January 4, 2010, 01:36 PM
I'd look at:

1. The gas piston. Make certain that the port is open and isn't getting closed or even partially closed from recoil. The hole in the barrel should be clean. The gas nut should be tightened firmly, but not super-tight. Make sure the gas piston is clean and can freely float forwards/backwards in the housing if the op-rod is out of the way.

2. The op rod. Make sure it moves freely in the op rod guide, and that the op rod spring guide is not causing the op rod spring to bind. If you have a flat op rod spring guide, replace it with a match-style one that has a cylinder profile. Sadlak makes a good one. This prevents the spring from binding or stacking. Make sure the op rod's tab slides freely in the channel on the side of the receiver. Grease this.

Jimro
January 4, 2010, 02:36 PM
Stovepiping means that the bolt isn't going fully rearward.

All the places to check have been mentioned except one, trying different ammo.

I don't know what ammo your neighbor is using, but if he isn't using M80 ball he isn't using the ammo that the factory is likely using to test for functionality.

Find out what ammo your neighbor is using to see if that might be the problem.

Jimro

Slamfire
January 4, 2010, 02:55 PM
Stovepiping means that the bolt isn't going fully rearward.

All the places to check have been mentioned except one, trying different ammo.

I don't know what ammo your neighbor is using, but if he isn't using M80 ball he isn't using the ammo that the factory is likely using to test for functionality.

Find out what ammo your neighbor is using to see if that might be the problem.


It could be going all the way back and then moving forward faster than the case clears the port.

I have never seen this, but if someone was using light magnum ammo in this rifle, it could be overaccelerating the gas system.

I suspect an extractor/ejector problem. If extractor tension is weak, the round could be dropping off the bolt face.

hagar
January 4, 2010, 03:33 PM
Could be caused by the gas plug as well. I bought a loaded M1A, and it did the same. Turns out the rifle had a gas plug in that was meant for shooting hot loads at 600/1000 yards, and did not function with my mild loads. The seller actually provided me with the original gas plug as well, and once I installed that, it worked like a charm.

Huck1969
January 5, 2010, 09:48 AM
Thank you all for taking the time to provide many suggestions and I will start working through the list with my friend. I should have posted previously that he is using Federal Gold Medal factory loads, usually Match with 168 Sierra's and has used Winchester 150 fmj's also. The problem persists with all ammo. Once again, thanks. Jim